The Chicken or the Egg or the Dinosaur?

If we accept what scientists tell us, and we usually do, a chicken is really a modified dinosaur. If that’s tough to stomach, how about the report that a group of scientists has managed to turn a chicken’s beak — a piece of critical avian equipment that appeared relatively late in the evolution of dinosaur to bird — back into something resembling the dinosaur snout it once was.

Bhart-Anjan Bhullar of Yale, who led the eight-year project along with Arhat Abzhanov of Harvard, insisted that turning a chicken into a Velociraptor was not the point. “Our goal here was to understand the molecular underpinnings of an important evolutionary transition,” Dr. Bhullar said in a statement, “not to create a ‘dino-chicken’ simply for the sake of it.”

Ah, but once a term like that is released, there is no stopping the image of a murderous dino-chicken escaping from an ivy-covered campus and wreaking vengeance on KFC. And popular science magazines were not able to resist headlines like “Dinosaurs of a Feather” or “How the Beak Was Born.”

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A rendition of the dinosaur Anchiornis, left, and a tinamou, a primitive modern bird. Snouts are rendered transparent to show bone differences.CreditJohn Conway

As reported in the journal Evolution, the goal of the research was to study the evolutionary process that gradually transformed flying dinosaurs into the thousands of species of birds on Earth today. Specifically, they asked whether an evolutionary change in proteins produced by embryonic cells might have allowed birds to fuse common face bones into what became beaks. By blocking the genetic signal that told the embryo to build a beak, the scientists caused the embryo to grow a snout that resembled those sported by their dinosaur ancestors. No beakless chicken was actually hatched.

But one could be someday — sporting a dinosaur tail on the other end, if John Horner, a paleontologist at Montana State University, succeeds in his project to restore the long tail that was replaced by mere feathers on birds somewhere along the evolutionary trail.

Dr. Horner envisions more, even the creation of new kinds of animals. Back in 2009, he and James Gorman, a science reporter at The New York Times, wrote a book called “How to Build a Dinosaur: The New Science of Reverse Evolution.” Dr. Bhullar insists that he is interested only in studying how evolution works. That may be just as well, because among his current studies are the unusual lower limbs of the crocodile.

The monstrous creature brought back to life is as old as human storytelling, and the temptation to invoke monster chickens or long-legged crocodiles continues to be irresistible. What may be truly amazing in the story of the dino-chicken, however, is what it tells us about the extraordinary ingenuity of science to plumb the tiniest mysteries of our universe, and the boundless curiosity of scientists who can dedicate years of their lives to something as seemingly arcane, but ultimately fascinating, as the genesis of a chicken’s beak.